Human behavior is of fundamental importance not only to the individual, but to the community and all of humanity. Now that humans have acquired the capability of interfering with or destroying living systems, it is of great consequence to the planet itself. With this in mind, the book Understanding Human Behavior: Theories, Patterns, and Developments is the result of inviting several leading innovative thinkers to consider how they could contribute to a discussion of understanding human behavior. Their perspectives differ in approach and focus, but they all confirm the great complexity of the topic, and they show that science has hardly scratched its surface. The eight chapters of this volume are dominated by considerations of how the behavior of humans began and developed in the distant past, during the evolution of early humans. In human sociology, the term behavior refers to the range of physical action/reaction and observable emotion associated with individuals today, as well as human society as a whole. But this describes only effects or symptoms of a condition pertaining to today, without considering how it came about, i.e., its original causes. This is examined in several chapters of this book, together with apparent historical trajectories of human behavior in an attempt to explore its etiology. Other contributions investigate more specific aspects of human behavior, including those recorded in history and even in modern times. In summary, this volume provides a well-rounded investigation into current cutting-edge understanding of the origins and nature of human behavior.